Photographic color developing compositions are used to process color photographic materials such as color photographic films and papers to provide the desired color images. Such compositions generally contain developing agents, for example 4-amino-3-methyl-N-(.beta.-methanesulfonamidoethyl)aniline, as reducing agents to react with suitable color forming couplers to form the desired dyes. However, such developing agents are susceptible to oxidation by dissolved oxygen. An antioxidant is conventionally included in the developer compositions to preserve the oxidation state of the color developer and thereby maintain useful color developer activity.
Many classes of compounds have been employed as color developer solution antioxidants, including hydroxylamines, hydroxamic acids, oximes, nitroxy radicals, hydrazines, hydrazides, phenols, saccharides, various simple amines, polyamines, quaternary ammonium salts, .alpha.-hydroxy ketones, alcohols, diamides and disulfonamides. To be used in practice, however, antioxidants must be soluble in aqueous media, non-toxic to living organisms, low cost and non-silver halide developers. Further, it is desirable that antioxidants react slowly with oxygen and rapidly with oxidized color developer, but not so rapidly that color development is suppressed. Yet another concern is that the antioxidant must not be able to promote bacterial growth.
All of these considerations greatly limit the number and classes of compounds that practically can be used as antioxidants or stabilizers in color developer solutions. The compounds most often used as antioxidants are hydroxylamines. They exhibit excellent characteristics by having a slow rate of aerial oxidation, being non-silver halide developers, and are relatively inexpensive to produce. There are considerable publications describing such compounds.
While there is considerable literature describing various water-soluble hydroxylamines that can be used as antioxidants, most of them have a number of disadvantages. For example, making them with the requisite solubilizing groups may be difficult or expensive. In addition, even when generally water-soluble, they may still emit an unpleasant odor that is offensive to users in the photoprocessing industry.
In addition, the conventional hydroxylamine functionality, being a strong reducing agent, will undergo reaction with oxygen and is therefore difficult to stabilize for extended periods of time outside of a ring-closed form.
Thus, there remains a need to find relatively inexpensive, odorless and effective antioxidants for color developer compositions.
Benzisoxazolones are known for a number of uses, including antimicrobial and antileukemic effects [Wierenga et al, J. Med. Chem., 27, 1212 (1984)] and as hair colorants (GB 1,255,452). In addition, they have been used in photographic emulsion layers for in-camera processing needs (see for example, U.S. Pat. No. 4,139,379 of Chasman et al, U.S. Pat. No. 4,192,679 of Erickson, U.S. Pat. No. 4,199,354 of Hinshaw et al, U.S. Pat. No. 4,199,355 of Hinshaw et al, U.S. Pat. No. 4,278,598 of Hinshaw et al and U.S. Pat. No. 4,609,610 of Dunlap et al), for scavenging oxidized developer within emulsion layers (see U.S. Pat. No. 4,192,678 of Chasman et al).
Very early literature shows their use as color couplers in color developing compositions for forming yellow dyes (see U.S. Pat. No. 2,846,307 of Woolley). None of the literature, however, considers that they would be useful as antioxidants in combination with color photographic developers for processing photographic materials with incorporated color couplers.